What is tache noire?

Tache noire is a fungal disease that affects grapevines. It is caused by the fungus Guignardia bidwellii and is characterized by the appearance of black spots on grape leaves and fruit. These spots can vary in size and shape but are typically circular or oval.

Tache noire can be particularly damaging to grapevines as it can cause defoliation, reduced fruit quality, and yield loss. The fungus can overwinter in infected plant material and be spread in the spring through rain or irrigation.

Prevention and control of tache noire typically involve a combination of cultural and chemical methods. These may include removing infected plant material, practicing good canopy management, applying fungicides, and planting disease-resistant grapevine varieties.

Overall, tache noire is a significant concern for grape growers and can have a significant impact on vineyard health and productivity.